Process of treating combustible gases.



H. L DOHERTY. PROGESSMOF TREATING COMBUSTIBLE GASES.

APPLICATION FILED MAR. 31, 1909.

Patented July 19,1910.

a SHEETS-sum1' 1.

WITNESSES:

' Ha L. DOHERTY.

PROCESS o? TRBAHNC COMBUSTIBLE CAST-JC APPLICATIONr FILED MAR. s1, 1909.

PatCntCd July 19, 1910.

3 SHEETS--SHBET 2.

Wl T/V E 6191519:4

H. L. DOHBRTYY.A "PROCESS or HEATING COMBUSTIBLE GASES.l

APPLIUATI'ON FILED 11.53.31, 1909.

'Patented 311151.19, .1910.

3 SHEETS-SHEET 3.

En Y

W/TNESSES;

.useful improvements ing Combustible Gases,

unrrnnsrarnsr 'Hnivnv L normar-r,

a. Beit known that L HE'NRYIL. `lDornsmY, a

citizen of the 1United States, residin -at New VOrk and Stateof New York, have invented new and in Processes ofTreatof which the following is a specification.

.This invention relates to a process of producing gas, andconsists of a method of treatf jing combustible gases-(such as blast furnace gases and .what 1s known as Mond gas) containing an appreciable amount of carbon'dioxidby preheatingethe gas to a tem erature- 'suticzient to supply `the heat require forthe dissociation ofthe carbon -dioitid-or to a temperature as near-t such temperature as is.-.practicable.and then passing the fpre- .heated gas through thefuelbedof a down- Idraft producer, whereby, the contained carhon-dloxid is reduced to carbon -monox1d with theuproduetion of La gas nearly free A from carbon-dioxid and which is particutem peratu re.V work.

'- `larlysuitable'for use in gas vengine and .high

theV gas without.- the addition thereto of a large volu'ne of inert nitrogen such as is un` 'avoidably introduced -into the vgas in the method of carrying. out such treatment,

Y heretofore known;-

As is .well known, the Vpresence of any large amount of carbon dioXld in a combustible gas reduces, 'to a very appreciable extent, the ame temperature obtainable in the combustion of 'such gas. This is due to the fact that part of the heat developed'must go to raising the temperature ,of the inert and useless carbondioxid. As the specific heat of carbon doxid per'uni't volume is rendering* it Ivslow. and producing a slowwhen burned by VVhenfurnace gas' "-;`steam (in the -mann ally utilized) the carbon dioxid which 1s high this means that theheat available for 4 raising the temperature of the necessary elements of. the'combustion 'is materially reduced.' Besides carbon -dioxid hasa specific retarding actionon the combustion itself,

burning diffused fiame of large volume in'- Y stead of the concentrated .intense flame producedI by a rich gas free from carbon dioxid an adequate supply of air. -1 is burne to generate in which it is gener- 'atively free fromA Water va oF-DNnw YORK, n, ,YQU-

:enocnss or rnna'rmeconnnstrrntn Giens.

.ratenteaauly 19,1910.

always rreducing the efficiency of the Acombustion. As explained 'above-it 'acts to render'the4 combustion sluggish, and diffused, YThe result is that thev gases come into contact .with the co1n`parativel-y'cool.v tubes .of the boiler 60 before the gas has been thoroughly burned Their temperature is, in this way, quickly reduced below that necessary tdinaintain combustion. 'The 4result is that the iue gases generally show a considerable amount of 'un- 65 burned carbon monoxid.v In the'caseof so- .called Mond gas, which is a gas I'nade' by the use in the producer ofa largeamount of jwater, the effects of itscarboifdionid, are similar, although the `high content of hydro- 170 gen renders them less noticeable. The`aver'ge.composition of an iron blast furnace gas is, about, carbon monoxid`23'%," carbon dioXid 12%,"methane 2%, hydrogen 2%, water .vapor 3% andfnitrogen 58%. 75 Mond', gas has an average compositionyof, about,cai-b`0n monoxi'd 16%, carbon'dioxid 12.4%, methane 2.2%, hydrogen 24%, 'nitro- The analysis given of the vMond gas is lfor the cooledA gasrwhich is therefrec'omparor.` gas is. invariably 'cooled be oreleavingV the producer i apparatus 'for the purpose l"of" recovering the' ammonia wluch jcarries, 85 while the blastfurnace gas (when used to fire boilers) is always used. hot,the com parison of the cold Mond gifs with the hotzblast furnace gas 1s a perfectly fair one.

From-the facts mentioned. above we can see that the efficiency of the utilization o these gases, couldv be 4greatly improved byv eventhe simple removal of the lhigh propor- .tion lofl carbon clioxid. By my invention,"

however, .instead of removing the carbon d1-. 95

oxid, I decompose. it ,in contact with carbbn at a high temperature forming two' rnole cules of carbon monoxid for every molecule of carbon dioxid, thus actually enriching tbe gas and at the' same creasing its volume, as well as elirninatmg` the carbondioxid to a large extent.-

In the drawings Figure -1, is asection of an apparatus suitable for applying my'invention taken on a planefthrough the'lines 105- A. B, Fig. 5, A B' Figi/3,' and A B Fig. 4 Fig. 2 isa section through a recuperator,

`zhich "s functionally connected with the gas -resentV has lthe effect of 'decidedly 55 4 Since this r time appreciably inwater vapor. The {hotZair-water *vapor cur-L '-.rent after leaving the recuperator is introproducer, on 4a plane'through. the line H.. of Fig. 54 and Gf Hlof Fig. 1; Fig. 5 1s al diagrammatic plan of the-entire ap aratus,

l The Vmethod ot operation isf 'as fo owe:- Air 'entersthebottom flues of the recuperator 4 through the dampers1 2 and'f which regulatethevolume and distribution of the air passm g` `into the recuperaton "Passing through theair iues'of 4 the air comes' Ainto contact witha layer of waterzwhich i's main- .3oV v' 1v producer. 6,5 the' oxygen and partl ofthe watained'in the' necessary number f lines to insure proper saturation ofthe'jair current. j

f'The hot gas frornthe producerpasses" through the gas flues'enveloping the-aire lues, its" directioncof flow' being parallel to but opposite in direction" to the air current.

',The greater part ofthe sensibleheatwhich Ithe'fgascarrlesv out of the producerls thus returned to the'latterin the heated air 'and f parto .thegas producerj', through the pipe 5. l i- Passing'npward through the fuel bed interv of vthe air .current react vwith the. fuel nary manner.;,fThis gas passes oibrom fthe .1 These consist of a number of hor'zontal'sec v -cally ad]acent lines, so as to form continuous' 40' tions oinedf alternately frontil an ack vwith the'a jacent iiues above and' be uwz'so as to form l a continuous" return-bend .vtlvue. ,As

shown, the Vrecuperator has threesuch iiues but it .-is obvious -that the nuibersniay be either4 increased or diminished 'without 'd e-l parting. from thev principle involved. The air fines arelocated in and envelopedfby three larger parallel lues 9.- These^iues consist of horizontal sections" joinedalter-V natelyfront and back 'so as to form continui "1 ous return-bend fines. The hot'gas'from 'thet Mond producer, 6, enters'- the'l recuperator' through the pipe 7 and is'distrbu'ted to the lues 9 bythe vcross'iiue` 10. "The hot gas' passes .through the iues'9, surroundlng the air llues 8, a`nd .gives up most of its sensible heat to theair passing through lues 8.- Theair enters the recuperator 4through thedanlp'- ers 1,2 and 3, passes througlrthe dues 8 pfi the recuperator and thence to the producer 6. The` recuperator 4 has a'water-su'pplypipe 12 withconnections'13,;into the lowerl sections of flues 8. Valves 14: control the' How of water to the air lines. i

In order to maintain as high a tempera-l clirrent and gas current it is`desirable to se-' this reascn,.`I introduce the water to the'air .'iues -at'sucha point that the airl passing through'the iues is loaded with the proper .quantity of water; A,All the waterevaporated in each flue is, preferably, run into the uppermost water pan in use andthe pans below supplied by the overflow fromthis. Dams 15, inthe lines having water connectionsinsure the 'maintenance of a shallow layer owater in the tlues and thus form water pans of the .bottom of the sections. If the amount-of. evaporation is lower than is required, .wat er isv admitted to a section higher up 1n the recuperator. Drainpipes 16, are rovided to carry awayany excess o1 water rom the lower. flues.,L \1Thef.cooled Mond gas leaving 'the recuperator-then passes to the'ordinary scrubbin'g'towers, 1'(

18. and19, where the ammonia` is remove fromthe gas. These towers do not necessarily dider .from the ones atpresent in use.

hauster20 and fori-ed through the pipe l21 `to the recuperatr 22. This -recuperator isin realitytwo separate recuperators one yfor air. and the otherfor gas, built, side by side, within the same shell. The section shown in Figzl isthrqgh one of the-gas'flues, but the construction is identicalron the air'side. 23.is va Vcross connection between the two -gaslues24c and 25 so that the gas iiowing thro h 22 is divided between the two ues '24 an 25. The tlue's 24 and 25-are.madeu vof horizontal sections each section connecte alternately front and back with the vertireturn-bend fines. -Enveloping these tlues are return-bend lues 26 and 27 for th'e enriched gas. These latter lues are formed as shown by introducing staggered horizontal. b'aile Walls in the recuperator so as to make the gaseous current 'passing through 26 and 27take arpath parallel to but in the opposite direction to the current passing through ,24 and 25. v Y

28 is the air tlue and 29 the enveloping 'gasiue s: When the gas to be treated contains vonly such a proportiouof CO2 that ltherelimi- *nary superheating fof the gas is su cient'to furnishthe heat requisite 'for the dssocia'ition o f ltsCO,I the'addition of airto ythe gas 1s omitted. In thisjcasethe secondary air recu erator and superheater is omittedgf e T e. cold -Mond gas' and air passing-'fthe gas through the ues 24 and.25 'and the air `through the flue 28.-'through therecupera- .tor go .next to theirrespectivesllperheaters, 30 and'31l These are buil hin thesame tshell but are'so-arranged'f i-, thereis-no communication between the;` gas and' air ture differential, as possible, between the air.

sides. The.: vsection' shownv Fig. 1 .is

the iiue49 tothe flue"5 0,*`and'thence tothe P hot gas iiue ofthe air recu'peratorand Vfromthrough the gas superheater\30,but the construction of. 31 isprecisely the same principle. Thegas enters'a flue 32 on pass-V ing from thei recuperator. ThisA flue 32 extends' across 'the `full `interior widthof the superheaterestabli'shin communication with thes'ni'all' flues 33.

simply fire clay' iues of small interior dia'- meter piercing'the Walls 34 and-35 of the superheater, andv also tliebaiile wall736, and

establishing communication between 32 and the similar flue 32.- The `'gas-,enterix1g" the flue 32 passes' .through the tlues'33into `the tlue'32f, thence out through the-pipe 37 to the gas bustlepipe 38 of the enriching prod'ucer or reductor, 39. The, air passes in a similarnianner throughf-the' iiues lljgf the' air f superheater and through the pipe 415 to the air bustle-pipe 42," of producer 39.

'43 is a'pipe tapped `into the pipe 21 and diverting a portionl ofthe Mond gas to the burners 34A, of the superheaters. These burners have an' 'air passage 45,-witha daniper 46, regulating thefadmissionof air" thereto. Surroundiiigd is4 an-annu1ar passage 47 for the. passage of thegas. v-'The' air and gas mix an burnon! their entrance'. to the combustion flue` 48, the hot'products of combustion passingupward around the fines 33, over the bailie-wall`36 and. down lthrough that .to the`stack 51.' `flhe'lbuiuie-is vare connected'b'y'ia cross-flue 52, so that they areallsupplied vwith gas bythe pipeff.'v Gates or dempers '53 cont-roljtlie supply "of gas to the burners.

The .enriching producer, 39, may be vof an y type suitable for'opeiation 'with down dra t .man sha1 @niet me lin vthe manner" hereinbelow explained. In

the LPPltlS 4,Shownthe producer? has a' I V,re ractory material andfha 'ngfla'refractory roof. or

arch to the fuel chamber.' Suitable poke-4 holes, 54 and 55, are provided for giving access to the vinterior of the producer, A

u charging devicetl, is provided for introducing the fuel into the producer. The

. highly heated Mond gas that is to be treated (enriched) is introduced into theupper part.

' of the fuel chamber through the'bustle-pipe 38 and connections57. The heated air usually necessary tol-maintain thel reaction in the producer' isV introduced- .through the,

bustle-pipe 42 and connections `58, the inner portions of the latter beingof refractory material.

The temperature in athe fuel chamber being 'maintained at a high ppint a portion of the Mond gas 4is burned by the oxygen of the air, with the probable' formation of Water va orand carbon'l monoxid.

VOwing tothe hig proportion of hydrogen in theMond gas and thehigh velocity of the reaction between that element and oxygen it is probable that the oxygen of .theair int-rohese flues 33 are chamber ofthe producer,-39, carrying the -burned in; upper part of 39 is about 3280 11:

duced burns principally according 'to the reaction, I 'I (l) 2H2+O2=2H2O Vrather-than according 'to the reaction, 70

Sincetlie products of these coinbustions are' dissociated again in the fuel bed of the proyd u'cer,by the respect-ive reactions, '75

the'net heat developed'is the' same ineach case, since 'it is that' due to the burning of equal weightsof carbon to carbon rnonoxid4 It isltherefore a matter of indifference which 'reaction predominates. :.aTThe gases from the upper. combustion carbon dioxid introduced with the Mondor blast furnace gasand the water vapor and carbon ldioizid produced bythe combustion in theupper part of 39, pass downward-and. into the fuel bed of the producer.. 4Here the highlyjincandescent carbon reacts with the' `Water vapor and carbon dioxid according to Areactions 3 'and 4. .In the case of the water vapor and carbon nionoxid formed from the artial combustion of the gas, they have, in the,y combustion' itself, furnished enough heat for their subsequent dissociation; Moreover, 'owing-to` the fact that the oxygen of lthe Water and one-half of that of -th'e 'carbon-.100

doxid burnsa portion of the fuel vto carbon monoxid the net result of the combustion of the hydrogen and carbon inonoxid and their subsequent dissociation is to liberate anv B2 T. per pound of oxygen reactinff, thereis required theoretically to maintain the fuel 16GoV bed of the enriching producer 2-8-6=.1488,

tin-say, 1/2l pound of oxygen for every,12| one pound of carbon dioxid introduced with the Mondor blast furnace gas. This is' on the assumption ,that the air and gas tenter the producer 39 at the temperature of the fuelbed therein, say, 1700 to 1800o F.' 12 Now, b the preferred method oft'reatment, which. .have hereinlrevealed, .I- introduce the gas and air at the highest racticable temperature,'say 2500 F. By this device I, at the expense of burning a small quantity 1 ofthe untreated Mond gas, supply-toitlie `gaseous currents previous to then' introduc- 1 'tion into the producer' 39', about 65% of the heat necessary for'' the dissociation of they carbon dioxidof the Mond gas. As aresult.

4I' have. reduced the theoretical'amount of air.

necessarytoimaintain the-temperature; in; 39

A"totht corres'pending tol/5 pound; of oxygen per pound' of' carbon dioxld, or, say, lone pound of air`per pound-of carbon dioxid originally present in the Mondor blast fun.

.'na'ce gas. AThis would correspond to about.

duction losses, liox'vevjer, it is necessary' in A:practice touSe atleast 25 ou. i"t, of air' per than-.Mondlgas o f normal composition "the n j lien the 'CO2 ofthe gas 'is 'c 'ompara'tively' lovv, itbec'omes possible to cut out the aux.

iliary'air entirely and to maintain the reactionssin the enriching'producerentirely I other The cooln the crude Mond gas, or

er-it leaves the producer 1n gas; a

` vvffhi'cliit was made shouldwhere practicable,-

be;v carried below' 212 Fab. so as to vcon'- den'se andremove fromthe'gasall the steamA or water-possible?4 The-presence of steamfin. the Vgaseoxjis current introduced into the' en.

riching producer is in thehghest degree ohjectionable and isj'to b'e'avoidedl to the greatest ossible extent.

sing the proportions of air and gas i'ven, the finished gas would have about the ollowing composition2 viz.: carbon dioxid,..

2.05 %;-carbon monoxid, 27.2%; hydrogen,

19.65%; methane, 1.8%; nitrogen, 49.3%.

The, gas would, at Lthe same time, be 1n-v creased' volume by 4about 20% and the ,'calorific power per cufft. by, about, 10 to i *12%@5 One of the difficulties vluaretofore encoun-l':

'i tered in the enrichment of 'gases containing the.

carbon dioiridhas been, that,-owing to the necessity o'f introduclno air into orwith 'the'. as `to .maintain the temperature in ielbed-of the secondary or enrich l producer at a reacting temperacure, part fof 'the gas was, of necessity, burned'in the 1 :`.l'owr part of the fuel b`ed',-with the production of a high temperature at thatzone 'where` the ratio of ash to fuel is high and the consequent fusion Vor sintering of the ash. addition, Where the heat developed by the combustion o,the oxygen Iof the air. adr'nittedl tothefprduc'er, has, alone, been4 relied'up'o'n to maintain ythe temperature of thefuelbed, the large amount of nitrogen 'tliatrnusg orhecessit-'be introduced with its carbon diozrid, the as following oii the local high tem erature caused bythe combustion between t e crude 'the in a treated gas :having-u,-` caloricf'value no higher, ifas high-as the.

my j improved method 'which I have I -herein.revealed, and claimed, I-make no Aattempt accomplish what is in fact imprac- `t-ic ab le, i. 6. 'the simultaneous introduction-V into a, bed Y of 4ignited" fuel. of a combustible gas containing f an. appreciable amount of carbon 'dioirid andthe air necessary forl the i generati-'on of sufficient heat to balanceI the endothermi'cf reaction which takes place with 'without v burning part ofthe combustible yconstituents of.V suchl gas. j In m vmethod it is a matter o findiierence whet erthe heat for I namtaning ,the dissociating reactions is generated by the combustion of artjf vthe gas itselfzorthe carbon of the fue` bed, since the net thermalresult isthe sam'e in either case. Infmy method, it is true', I develop a s high, Ior.ev e1 1lhigher, temperature in the reductor or' secondary, producer. at the' point .of-introduction of the" .as and air, but I do soA undercondit'ionsw high temperatureto -facilitate the 'operation' "of the producer' rather than retard the -Same.

.By introducing .the as and air at the upper suriacezoi the .fuelQ ed'V the loealtem perature developed becomes; an advantage.

By thisadevice, theozreshly `chargedjzfilel is immediatel subjectedl to a. temperature .whichquicglyfdistils 'ofi its volatile c olnstituents, whichmust. of necessity 'pass Vthrough thewhole depth ofth'e fuel bed. The result'is that .the "tarryv Yvapors 'are wholl broken down into permanent gases, whic addgreatly to the illuminating and calorific powerl of the gas when. a bituxnntufsii-l coal is -used in fthe reductor. It has, heretofore, been found very difficult to Vmake# hse of bituminous coal owing to the difficulties caused lby thet'arry'substances carried in suspension .in theygas.v I -1 In the heretofore proposed methods of treating blast furnace as for reduetionof diiiculties 'mentioned gas and the admixed air ar'ev not due to thfe l high temperature 0f.itself,but to thedocaj l.development of such hi h` temperature'in heat 'they may be 'subected .since they an isolatedA from one another. 'JQhey may b more,` 'or' lesscompletely fused-without th "least danger of them agglomerating together to form clinker 'or slag. If then we introduce. the combustible gas containing carbon dioxid, and 'the airrequired to t ter of indifference how high a temperature is produced. The temperature maybe as .high as it will and, yet, not cause any sin 1 tering or clinkering of the ash'. With a suiiicient depth of fuel there is, practically, no danger of the high temperature ofthe hottest layers`0f the fuel bed extending to, the

ash zone of the reductor, for the water vapor or carbon dioxid formed by the combus tion, mentioned, in its passage through the fuel bed is again dissociated withthe absorptionof heat. *There is, therefore, a progressive diminution of temperature from the top to the bottom of the fuelbed. The heat:

develo ed due to the reaction of the gas and airjt'a esplace in immediate contact with theA part ofthe fuel bed whose potential re- 'l active energy is the greatest. The higher,l

the. temperature` atgwhich the gases come into' contact`with the -fuel the greater'rvill ,be the speed and energy'oftheendothermic fuel bed at that point and permits it to recover' its normal. temperature. This selfandthe velocity at which the current is.

temperature and balancing action of tlie exothermic and endothcrmic reactions has a tendency to keep a much greater depth .of the fuel bed at a reactive temperature than is the case in or# dinary\ practi With any given proportion ofa'ir and;7e they are passe' ti`` gh the fuel bed, there is, thus, a tendency to establish a definite downward temperature graduation in the massof fuel. `Idy propegly regulating the proportion of air to gas forced through the fuel bed, it is possible to maintain the temperature conditions 1n the producer at any desired point. l

y .The high temperature in the 'upper part of the fuelbcd has an incidental advantage which considerably facilitates the operation of thefenriching producer or reductor. The result of the high temperature is that the ash particlesare f11sed"\vithin their carbo# nac'eous envelop. As the burningfuel sinks through the shaft of the producer, it is beermallyA balance its reactionwth tnercarbon, of the fuel, in contact with the yunbuinedfuel in stead of-in contact -With the ash, itis a matopmentof an excessive temperature in any as and agivcn rate at which coming,cntinually, cooler and cooleruntil by the time the carbonaceous envelop of the ash particles hasbeen hurned away -it has reached temperature-below the fusing ointoflthe ash. The result is, that the ash instead of consisting'ofhalf 'fused masses of clinlrer, is of a decidedly sandy'orgranular nature, which greatly facilitates its removal from the producer, as well as keeps the ash'bed in anfopenporous condition.

` By introducing an' eflicient recuperator -andevaporator between the Mond producer (Where the crude gas is Mond gas instead of 'blast furnace gas) and the absorption towers I am able to restore-to the Mond producer a mach, larger proportion of the heat 'carried ont of itby the gas Vthan `can bev done inthe ordinary method of working.. Besidesl the additional heat recovered enl 'ables me to dissociate-more Water 111l the producerwith-"the` result of producing a richer gas'.` 'l While in the foregoing description, I have selectedfor the purpose ofv illustrating my invention'its 'spec'c application to Mond gas, it is evident that the process may be applied to the treatment of yany combustible lgas `containing reducible quantitiesjof carL bon fdioxid; that is', quantities sutliciently large to 'permita useful amount of reduction by contact with hot carbon.

Where, as in the-caseof the treatment of blast furnace gas, the volume'o `gas is very large it is often advisabletouse severalreductor producersifor treating the gas rather than asingle one. When this is'done I may either pass the z.gas through the producers in parallel (to borrow an electrical term)' or 1n series, as may seem most desirable.

A great advantage of my method is, that I am enabled to use bituminous coals in the roducer instead of coke or anthracite. vThe igh temperature in the upper part of my fuel bedpand the fact that the productsl of distillation must, of necessity, pas's through the whole mass `of incandescent fuel insures a perfect breaking downofthe hydrocarbon vapors into permanent gases, thus avoiding any trouble due tothe tarry va.pors'that .are ordinariily found in the gas when bituminous coals are used. Owing tothis fact that can make use of bituminous coal I cbtair a vgas having a much higher illuminating value than ordinary producer gas.

Where the gas is to heused` for firing furnaccs-suchas reheatingfurnaces for en;4 `amplethis feature ofA my inventlon' 1s o:

very great importance. The hydrocarbon:

of the coal have apractical enriching valu| =far in excess of the actual increase Whil they cause in the caloriic Value of the gas .This is dueto the fact that. they cause th gas to burn with a flaming effect which' bj increasing the radiant eifect of the combus transmitte -to the charge in the e' o Y 964,520.1

tiongreatl furnace. What I claim 'and desireto secure by Letters Patent is:-' Y 1. The process of improving a combustible gas containing substantial quantities of,

.reducible carbon dioxid which. consists in passing sucnco'inbustible gas, in admixture with air throu h aldeep bed of'ignitedfuel in a down-.dra producer, the roportion of -air admixed withsaid gasbeing-restricted 'fte the quantity required to maintain the fuel bed in s`a1d producer at' a'reacting tempera-l ture ,bycounterbalancing the cooling diie tol the reaction of4 said'carbon; dioxid" upon said fuel. i; f f 2. The', process of-l treating a combusti 'b le gas containingearbon-dioxid, which con- 'sists in removing from 'said' gas substan tially all of its condensiblef water-vapor,

'superheating said gas, fand-passing said superh'eated gas through the fuel-bed of an sists in removing-from said'gassubstantially' through a bed of-iiicandescentjfuel in af gas producer, sufficient air be A ingfmixed with said superheated gasv before tain the latter at a'teinp'eratiire suituble'for;

down-draft producerfsaidl fuel bedvbeing;

maintained at a temperature capable ofreducingcarbon AdioXid. i

-3.-'1`he process oftreating a combustible gas containing: carbondioxid which con .all 'of itsl condensible water-vapor,A superheating -tliemajorportion l of said gas. by burning'theminorportion of said gas ina suitable'superheatei, andpassing the .su erheated "gas downward through u a 4deep ed of fuel in a suitable-inclosedclianiber5 said, fuel bedfbeiiig maintained at a sutieientl-yv high temperature to reduce the {carbon-d1- oxid of said gas by'adding to said gas,`pre

vious to passing the saine through said fuelv ren'tliat bed, theminimum quantityof oxyg will maintain said -fuel bed'at the desired temperature.

4. The process of improving aeoiiibusti b le gas containing carbon-diend, lwhich coiiv sists in cooling said gas below- 212` Fab. whereby thev major portion of the water va-iv por contained by said gas is condensed therefrom, passing the major ortion ofrsaid 'gas through a superheater2 urningv the minor portion of said gas 1n saidV superheater, wherebythe said major` portion of -the 4gas.

is heated-'to a ".high temperature, and continuously passing lie-Said s'uperlieatedV gas downsdraft its passage throughthe fuelbed-.tofmaiuthe reductionof moregorlerss ofthe carbon dioxid Aintroduced into the producer, and.

1that formed thei-ein,'to carbon inonoxid,1the

, thickness ..offthe Iuel bed', and the velocity of I '.th'e drafteurrent-beingso regulated that the reduction of the carbon-dioxid'to, inonorid is carried on to the extent desired `up the'.

increases the quantity ofvheat, .p

' heated gas a` heaterg'in burning a minor portion of said gas in said superheater, whereby the 'temperature of the-major porto'nof'said gas is raised to 'a temperature superior tojthe temerature of reaction betweenisaid non-coiniiustible constituents and 'carbon,"in' introducing said heated gas above the fuel bedl 'of a. down-draft-producei', in` adding to said o rtonof air, said air' having been previous y heated by(v a portion 'of the products of combustion' from `the said minor portion of said combustible-gas, in passing the 'resulting-:gases downwardtli'rough the fuel'be'd insaidprodiieen'whereby the noncombustible 'ases formed' by .the air adinittd and t 'efreducible non combustible gases of 'the Qsaidcombustible gas,V are vreduced to lcc'mibustib-le` gases by reaction with the saidffuelbed.j :in-.withdrawing the enriched gas frfoin the lower'part of vsaidproducer', andinfpassin'g it through the reculperator for heating Vthe unenriiched gas.

. TheL process 'of 'iniilring a rich producer gas which consists' inheatiiig 'air in ia' recu- ,pi'ator bythefsensible heat'of hotf'producer gasfin introducing an excess of watervapor into said heated "air, in passing the current ofjheated Aair and-.water vapor through a. bed of 'incandescent'y fxiel, `\v-liereby a producer gas ,is inadejcontiiiniiig i'ediicl'ble' 'noiilcoinvbustib'le cons tituents,' in passing said producer gas -through said, re: .-.}iperator to heat another portion ofair, in recovering the anirnonia from. said. ga@ iii heatingl the major portion of said. gas freed from .unuioiii-li 1n a recuperatornheated by a previously enriched t portion o f said gas, iii'bui'ning n 'minor' portion ofsaid gas4 tolieat a superheater, in

passing-- the', iiiajorportion of said, gas through said,l superheater whereby its teinfperature is ruisedto a point superior to that Y at .which thefredueihle non-co`i`nbiistible constituents of `:the as will react with carbon, in introducinfIr saidinajor portion fof the gas into a doivnraft producer;I inpassing said heated gas. through. theffuel bed of'said produeer, whereby more orles's'b'f therediicible y Vnon-combii stible constituents of saidgas are reducedito combustible constituents, in withdrawin the s o 'enriched 4gas from the lower part o said own-draft lpro'ducerand in passingfit'thro, h Vthe'said recuperator to eat another p ortion-of gas,

' said fuel 7.. The process of improving combustible gas containing substantlal'amounts of redueible carbon dioxid by the reduction of said 'carbon Adioxid Which comprises heating such a gas to a temperature suliicient to compensate at least in part for the endotherinie action of the contained carbon dioxid upon fuel and downward through a deep bed of ignited fuel `together with merely 4suiicient air to counterbalance any uncompensated endothermic action of said carbon dioxid upon 8l The process of making gas whiplriicom`- prises producing Mond gas containing hydrogen and substantial amounts of carbon dioxid, recovering the ammonia ltherefrom,

rehei'iting the gas to a temperature sufficient to compensate at least in part for the endothernne action of the contained carbon di# oxid upon fuei, passing the heated gas downward through a deep bed of ignited fuel together with merely sufficient air to counterbalance any uncompensated endothermic acpassng the heated gas New Yorkand State tion and recovering the heat of outgoing gas to add to ingolng. n

9. The` process of improving combustible gas containing substantial amounts of carbon dioxid which comprises heating such gas by recovered heat from treated gas, superheating Aby heatfrom combustion of a portion oi gas, passing said gasdownward through a deepfbed of ignitedfuel in a secondary' producer or reductor and recovering the heat from .the treated gas to add to untreated gas, air being added to the gas prior to treatment 'in the reductor in the amount suiiicient to for by the sensible heat of such gas.

Signed at New York `eity, in the county of of New York, this 30th day of March, 1909.

HENRY DGHERTY.

.ou'nterbalance any endothermic .cooling of the reductor fuel not compensated 

